CN102405389B - Method and apparatus for cooling down a cryogenic heat exchanger and method of liquefying a hydrocarbon stream - Google Patents
Method and apparatus for cooling down a cryogenic heat exchanger and method of liquefying a hydrocarbon stream Download PDFInfo
- Publication number
- CN102405389B CN102405389B CN200980104368.XA CN200980104368A CN102405389B CN 102405389 B CN102405389 B CN 102405389B CN 200980104368 A CN200980104368 A CN 200980104368A CN 102405389 B CN102405389 B CN 102405389B
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- cold
- producing medium
- heat exchanger
- module
- cryogenic heat
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- 238000001816 cooling Methods 0.000 title claims abstract description 118
- 238000000034 method Methods 0.000 title claims abstract description 64
- 239000004215 Carbon black (E152) Substances 0.000 title claims description 103
- 229930195733 hydrocarbon Natural products 0.000 title claims description 102
- 150000002430 hydrocarbons Chemical class 0.000 title claims description 102
- 238000004891 communication Methods 0.000 claims abstract description 41
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- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical group C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 79
- 239000003507 refrigerant Substances 0.000 claims description 75
- 239000007788 liquid Substances 0.000 claims description 41
- 238000009833 condensation Methods 0.000 claims description 37
- 230000005494 condensation Effects 0.000 claims description 37
- 230000008859 change Effects 0.000 claims description 29
- 238000005057 refrigeration Methods 0.000 claims description 26
- 239000003345 natural gas Substances 0.000 claims description 23
- 239000007789 gas Substances 0.000 claims description 16
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- 239000000203 mixture Substances 0.000 description 18
- 238000012360 testing method Methods 0.000 description 18
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- 238000007906 compression Methods 0.000 description 13
- 230000006835 compression Effects 0.000 description 13
- 238000010586 diagram Methods 0.000 description 12
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- 239000003949 liquefied natural gas Substances 0.000 description 10
- 230000001276 controlling effect Effects 0.000 description 8
- 230000033228 biological regulation Effects 0.000 description 7
- 238000012544 monitoring process Methods 0.000 description 7
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- 238000005259 measurement Methods 0.000 description 6
- 238000003860 storage Methods 0.000 description 6
- 238000004781 supercooling Methods 0.000 description 6
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- 238000012545 processing Methods 0.000 description 5
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- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 4
- 239000000284 extract Substances 0.000 description 4
- 239000012530 fluid Substances 0.000 description 4
- 238000005194 fractionation Methods 0.000 description 4
- 239000001273 butane Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- IJDNQMDRQITEOD-UHFFFAOYSA-N n-butane Chemical compound CCCC IJDNQMDRQITEOD-UHFFFAOYSA-N 0.000 description 3
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- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- -1 comprises methane Chemical compound 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 239000000110 cooling liquid Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
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- 239000002737 fuel gas Substances 0.000 description 1
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 description 1
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- 238000012423 maintenance Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 1
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- 238000012887 quadratic function Methods 0.000 description 1
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- 230000008961 swelling Effects 0.000 description 1
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0211—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle
- F25J1/0214—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a dual level refrigeration cascade with at least one MCR cycle
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/0002—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the fluid to be liquefied
- F25J1/0022—Hydrocarbons, e.g. natural gas
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/003—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production
- F25J1/0047—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle
- F25J1/0052—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle by vaporising a liquid refrigerant stream
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/003—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production
- F25J1/0047—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle
- F25J1/0052—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle by vaporising a liquid refrigerant stream
- F25J1/0055—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle by vaporising a liquid refrigerant stream originating from an incorporated cascade
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/006—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the refrigerant fluid used
- F25J1/008—Hydrocarbons
- F25J1/0087—Propane; Propylene
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0211—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle
- F25J1/0214—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a dual level refrigeration cascade with at least one MCR cycle
- F25J1/0215—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a dual level refrigeration cascade with at least one MCR cycle with one SCR cycle
- F25J1/0216—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a dual level refrigeration cascade with at least one MCR cycle with one SCR cycle using a C3 pre-cooling cycle
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0228—Coupling of the liquefaction unit to other units or processes, so-called integrated processes
- F25J1/0235—Heat exchange integration
- F25J1/0237—Heat exchange integration integrating refrigeration provided for liquefaction and purification/treatment of the gas to be liquefied, e.g. heavy hydrocarbon removal from natural gas
- F25J1/0238—Purification or treatment step is integrated within one refrigeration cycle only, i.e. the same or single refrigeration cycle provides feed gas cooling (if present) and overhead gas cooling
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0244—Operation; Control and regulation; Instrumentation
- F25J1/0245—Different modes, i.e. 'runs', of operation; Process control
- F25J1/0247—Different modes, i.e. 'runs', of operation; Process control start-up of the process
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0244—Operation; Control and regulation; Instrumentation
- F25J1/0245—Different modes, i.e. 'runs', of operation; Process control
- F25J1/0249—Controlling refrigerant inventory, i.e. composition or quantity
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0279—Compression of refrigerant or internal recycle fluid, e.g. kind of compressor, accumulator, suction drum etc.
- F25J1/0281—Compression of refrigerant or internal recycle fluid, e.g. kind of compressor, accumulator, suction drum etc. characterised by the type of prime driver, e.g. hot gas expander
- F25J1/0283—Gas turbine as the prime mechanical driver
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0279—Compression of refrigerant or internal recycle fluid, e.g. kind of compressor, accumulator, suction drum etc.
- F25J1/0285—Combination of different types of drivers mechanically coupled to the same refrigerant compressor, possibly split on multiple compressor casings
- F25J1/0287—Combination of different types of drivers mechanically coupled to the same refrigerant compressor, possibly split on multiple compressor casings including an electrical motor
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0279—Compression of refrigerant or internal recycle fluid, e.g. kind of compressor, accumulator, suction drum etc.
- F25J1/0292—Refrigerant compression by cold or cryogenic suction of the refrigerant gas
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0279—Compression of refrigerant or internal recycle fluid, e.g. kind of compressor, accumulator, suction drum etc.
- F25J1/0298—Safety aspects and control of the refrigerant compression system, e.g. anti-surge control
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2220/00—Processes or apparatus involving steps for the removal of impurities
- F25J2220/60—Separating impurities from natural gas, e.g. mercury, cyclic hydrocarbons
- F25J2220/64—Separating heavy hydrocarbons, e.g. NGL, LPG, C4+ hydrocarbons or heavy condensates in general
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2280/00—Control of the process or apparatus
- F25J2280/10—Control for or during start-up and cooling down of the installation
Abstract
Provided are a method and apparatus for cooling down a cryogenic heat exchanger, employing a programmable controller that receives input signals representing sensor signals of one or more controlled variables in a selected process, and produces control signals to control one or more manipulated variables in the selected process. The programmable controller can execute a computer program that comprises a network of at least three modules. The modules in the network are interconnected such a trigger signal received by a second and a third module of the at least three modules corresponds to a communication signal that is generated when the first module of the at least three modules has reached a pre-determined target for that module.
Description
Technical field
The present invention relates to a kind of method and apparatus for cooling cryogenic heat exchanger.
Here, in the special various embodiment that disclose, cryogenic heat exchanger is suitable for making hydrocarbon stream liquefaction, for example natural gas flow.
In yet another aspect, the present invention relates to a kind of method of this hydrocarbon stream that liquefies.
Background technology
The cryogenic heat exchanger of some types is known.Such cryogenic heat exchanger can the method for liquefied natural gas stream in, to generate liquefied natural gas (LNG).In this case, cryogenic heat exchanger can receive hydrocarbon stream to be liquefied conventionally, and can make hydrocarbon stream and the cold-producing medium of evaporation at least partly carry out heat exchange, thereby hydrocarbon stream is liquefied at least in part, and the hydrocarbon stream that can be expelled to small part liquefaction.
Residing stress level when the kind of hydrocarbon and hydrocarbon stream are by cryogenic heat exchanger in stream, for example natural gas start the representative temperature of liquefaction may be at-135 ℃.
But, prepare cooling and/or make the normal operating of hydrocarbon stream liquefaction before, must cooling cryogenic heat exchanger, for example, Zhe Shi factory starts a part for routine.
In order to prevent from destroying cryogenic heat exchanger, comprise the leakage that is for example distributed and caused by the thermal expansion on cryogenic heat exchanger and thermal contraction, the operator of cryogenic heat exchanger and producer's general recommendations avoid surpassing maximum temperature rate of change a certain regulation, in time as much as possible.
On the other hand, in order to minimize the unproductive or non-best productivity time limit of cryogenic heat exchanger, operator conventionally wishes with cooling their cryogenic heat exchanger of two-forty as far as possible.
United States Patent (USP) 4809154 has been described a kind of for controlling the automatic control system of hybrid refrigeration formulation liquefied natural gas (LNG) production facility, has wherein optimized functional parameter.By regulating parameter to realize optimization, described parameter comprises mix refrigerant quantity in stock, composition, compression ratio and compressor turbine speed, with the per unit energy to facility consumption, reaches the highest output of products value.
In more detail, the process controller system of United States Patent (USP) ' 154 is implemented with parallel processing computer, described parallel processing computer allows parallel control pending operation on multiprocessor, described multiprocessor can be accessed a common storage, wherein stores the value of the current state that represents each sensor relevant with production facility and each controller.For management parallel control process, to preserve request queue and return to queue and precedence table, described precedence table is for solving the conflict between operation repetitive process loop.
The process controller system of United States Patent (USP) ' 154 can play satisfactorily optimal number or the quality of the liquefied gas of optimizing or keeping producing when the operation of liquefaction operation.But the initial cooling period that the process controller system of United States Patent (USP) ' 154 is unsuitable for when starting is controlled cryogenic heat exchanger, because required pending step order can not be utilized precedence table and request queue and return to queue and process.
Summary of the invention
The invention provides a kind of equipment for cooling cryogenic heat exchanger, described cryogenic heat exchanger is suitable for making hydrocarbon stream liquefaction, for example make natural gas flow liquefaction, described cryogenic heat exchanger is arranged to receive hydrocarbon stream to be liquefied and cold-producing medium, and can make hydrocarbon stream and cold-producing medium carry out heat exchange, thereby make at least in part hydrocarbon stream liquefaction, and can be expelled to the hydrocarbon stream of small part liquefaction and by the cold-producing medium consuming of cryogenic heat exchanger, this equipment comprises:
-make consumed cold-producing medium recirculation get back to the cold-producing medium recirculation circuit of cryogenic heat exchanger, described cold-producing medium recirculation circuit at least includes compressor, compressor recycle valve, cooler and JT (joule-Tang Pusen) valve;
-mono-Programmable Logic Controller, it is arranged to
(i) receive the input signal of the sensor signal that represents one or more control variables;
(ii) generate control signal to control one or more manipulated variable; With
(iii) computer program, described computer program comprises the network with at least three modules, one or more in wherein said at least three modules receives one or more the expression in input signal, and generates one or more the expression in control signal;
And wherein said at least three modules are all arranged to:
(a) wait for, until receive a triggering signal; With
(b), when receiving triggering signal, start to carry out the predetermined sequence of one or more computer-readable instruction, at least until reach the predetermined module target of this module;
And, these module interconnects in network, the communication signal producing while making triggering signal correspondence that the second and the 3rd module in described at least three modules receives the first module in described at least three modules reach the predeterminated target of this module.
In yet another aspect, the invention provides a kind of method for cooling cryogenic heat exchanger, described cryogenic heat exchanger is suitable for making hydrocarbon stream liquefaction, natural gas flow for example, and the method comprising the steps of:
-cryogenic heat exchanger is provided, described cryogenic heat exchanger is arranged to receive hydrocarbon stream to be liquefied and cold-producing medium, and can make hydrocarbon stream and cold-producing medium carry out heat exchange, thereby make at least in part hydrocarbon stream liquefaction, and can be expelled to the hydrocarbon stream of small part liquefaction and by the cold-producing medium consuming of cryogenic heat exchanger
-the cold-producing medium recirculation circuit that makes consumed cold-producing medium recirculation get back to cryogenic heat exchanger is provided, described cold-producing medium recirculation circuit at least comprises a compressor, a compressor recycle valve, a cooler and one the one JT valve;
-activation one Programmable Logic Controller, described Programmable Logic Controller
(i) receive the input signal of the sensor signal that represents one or more control variables;
(ii) generate control signal to control one or more manipulated variable; With
(iii) carry out a computer program, described computer program comprises the network with at least three modules, one or more in wherein said at least three modules receives one or more the expression in input signal, and generates one or more the expression in control signal;
And each in wherein said at least three modules
(a) wait for, until receive a triggering signal; With
(b), when receiving triggering signal, start to carry out the predetermined sequence of one or more computer-readable instruction, at least until reach the predetermined module target of this module;
And, the first module in wherein said at least three modules produces a communication signal while reaching the predeterminated target of this module, described communication signal passes to the second and the 3rd module in described three or more modules, and there, communication signal serves as second and the triggering signal of the 3rd module.
Cryogenic heat exchanger in order on the equipment of the method that limits and/or above restriction cooling after, hydrocarbon stream can be liquefied in one or more step, comprises and makes hydrocarbon stream in cryogenic heat exchanger, carry out heat exchange, to generate liquefied hydrocarbon product.
Accompanying drawing explanation
Referring now to embodiment with subsidiary nonrestrictively schematically attempt, only give an example to the present invention with explanation, wherein:
Fig. 1 has shown the cryogenic heat exchanger configuration according to an embodiment with schematic diagram;
Fig. 2 has shown the cryogenic heat exchanger configuration according to another embodiment with schematic diagram;
Fig. 3 has shown the block diagram for the module of the cryogenic heat exchanger of automatic cooling Fig. 1 or Fig. 2 with schematic diagram;
Fig. 4 has shown according to main cryogenic heat exchanger configuration another embodiment of the present invention, for testing with schematic diagram;
Fig. 5 has shown the whole series configurations (line-up) of Fig. 4 with schematic diagram, show the temperature and pressure of monitoring;
Fig. 6 has shown that module for testing is together with the block diagram of the whole series configuration of Fig. 4; With
Fig. 7 has shown the alternative module structure in the block diagram that can be incorporated to Fig. 6 with schematic diagram.
The specific embodiment
For ease of describing, for the stream transporting on pipeline (pipeline) and this pipeline (pipeline) is given single reference number.Same reference number is indicated similar parts, stream or pipeline (pipeline).
Described method and apparatus has adopted a kind of Programmable Logic Controller, described Programmable Logic Controller receives the input signal of the sensor signal that represents one or more control variables in selected operation, and generates control signal to control one or more manipulated variable in selected operation.Programmable Logic Controller can be carried out a computer program, and described computer program comprises the network with at least three modules.
Be divided into so a plurality of modules and be convenient to manage more flexibly and more simply cooling process, and be convenient to safeguard Programmable Logic Controller.Each module can be handled one or more valve, and has at least one clear module target limiting.Module can operate independently of one another, but can have the public variable being detected by some modules, and these modules can be subject to the impact of the effect of more than one module.This modular method of the independent module of carrying out that adopts makes the present invention be suitable for cooling all types of heat exchangers automatically, comprises so-called coil-type and fin-type.
One or more in described at least three modules receives one or more the expression in input signal, and generates one or more the expression in control signal.Described at least three modules are all arranged to:
(a) wait for, until receive a triggering signal; With
(b), when receiving triggering signal, start to carry out the predetermined sequence of one or more computer-readable instruction, at least until realize the predetermined module target of this module.
Produce a communication signal, this mark this module and has been reached or realized predetermined module target.This communication signal can originally be produced in other places of Programmable Logic Controller by module, or it can comprise the sensor signal that for example represents in cryogenic heat exchanger or reached predetermined state around.Predetermined module target can be the intermediate object program for this module, and under these circumstances, module can continue to carry out more computer-readable instruction, for example, reach the other module target of computer.As selection, communication signal also can complete execution by mark module.
These module interconnects in network, the communication signal producing while making triggering signal correspondence that the second and the 3rd module in described at least three modules receives the first module in described at least three modules reach the predeterminated target of this module.
The mode of this interconnecting modules allows sequence flow to control, wherein, and before starting one or more other tasks, must complete at least one assignment of mission, and wherein, at least two tasks must be carried out one by one, and other tasks must be carried out simultaneously.
Do not need to manage the priority of each task, because each module all waited for before starting to carry out its task, until it receives a triggering signal, and after completing its task, it produces a communication signal.Completing of this task can represent by this communication signal, and this mark concerning this module, and the predeterminated target relevant to this task reaches.
Any signal that mark completes predetermined module target can pass to and then carry out one or more ensuing module of the task below one or more in sequence flow and/or one or more ensuing module of the task below can then carrying out one or more in sequence flow receives.When communication signal is received by two or more ensuing modules, these two or more ensuing module prepares to start their computer-readable instruction of executed in parallel.
For ease of explaining these claims and description, communication signal can produce after reaching target, or can be any signal that deducibility module accordingly makes it.
Be to be understood that, the second and/or the 3rd communication signal can produce when the second and/or the 3rd module has reached their module targets separately, and the described second and the 3rd communication signal can serve as the triggering signal of one or more subsequent module or in this process, use in another way.
The task of one chosen module may be in being controlled variable one or more on the constraint of a certain restrictive condition in carry out, and this one or more control variables is not subject to the control of described chosen module, but the control of other modules of for example simultaneously being moved.Under these circumstances, if the further execution of the task of chosen module can cause running counter to described restrictive condition, the execution of its task is by automatically delaying.When other modules that affect controlled variable are when carrying out its task, can stop this delay, restrictive condition be disengaged or change, thereby providing described chosen module further to advance the space of the execution of its task.
Thereby, the effect of the network structure of the module of advising be module design task if desired standard sequentially carry out and carry out if possible simultaneously, the standalone module that described network structure comprises mutual parallel work-flow, the control action of one in module is subject to the constraint of a variable thus, and described variable is subject to the impact of one or more manipulated variable of another module manipulation.This makes this generic module network can be suitable for admirably the cooling operation under some restrictive condition such as cryogenic heat exchanger.
In at least two interconnecting modules, select to be in addition, an event signal produces in a module, and this event signal is received by another module, and causes the variation of other operations of other modules except this module starting.For example, when causing that the first module of this event signal generation reaches a certain state, the parameter that this event signal can trigger in other modules changes.
The triggering signal that module network can make mark one particular module start to carry out predetermined instruction can be n the triggering signal being received by this module, and n can be any natural number here.For example, before chosen module can start to carry out its computer-readable instruction sequence, chosen module may need to wait for that for example other three modules realize their target, at this moment produces communication signal.Under these circumstances, its possibility is necessary to be waited for, until it receives three communication signals that serve as triggering signal, thereby in this example, two triggering signals early start to carry out the associated trigger signal of predetermined instruction sequence early than mark one particular module.
Programmable Logic Controller can be embedded into dcs (DCS), wherein, for example module provides output via interface server, the OLE for process control (OPC) (object linking and embedding) that for example can transmit between computer program and the various interface existing in DCS piece (interface blocks).In such configuration, DCS can recall the control of manipulated variable (for example selected valve), need not wait for Programmable Logic Controller transfer control, desirable during emergency etc.
The inventor of present patent application expects, this Programmable Logic Controller disclosing is here suitable for the automatically cooling of cryogenic heat exchanger ideally, and described cryogenic heat exchanger is suitable for making hydrocarbon stream liquefaction, for example natural gas flow.
Advantageously, cryogenic heat exchanger automatic cooling is convenient to, with the cooling cryogenic heat exchanger of high-temperature rate of change as far as possible, can not surpass the maximum temperature rate of change of regulation.Under manually controlling, during cooling cryogenic heat exchanger, operator must make to maintain wider surplus capacity between rate of temperature change and regulation maximum conventionally.
In addition, experience shows, in about 30% time, understands due to complicated operation, and by mistake surpasses the maximum temperature rate of change of stipulating.And due to automation described here, this percentage is estimated greatly to reduce.Inventor estimates, surpasses maximum temperature rate of change and can be reduced to for about 12% time (time), or be reduced to the time that is at least less than 15%.
In addition, method and apparatus disclosed here also can be for avoiding one or more space temperature gradient in cryogenic heat exchanger or around to surpass the maximum of recommending.
With for cooling parallel type cryogenic heat exchanger, compare, the advantage of method and apparatus described herein is more obviously for cooling reverse-flow cryogenic heat exchanger, preferably use external refrigerant, wherein the cold-producing medium of evaporation is with respect to the next cooling stream counter-current flow of cold-producing medium by evaporation at cryogenic heat exchanger.
Method and apparatus disclosed here has utilized so-called manipulated variable and control variables.In addition, optionally, also there is one or more monitored parameters.
In description and claims, term ' manipulated variable ' be used for represents to be subject to the variable of the control action of Programmable Logic Controller, and term ' control variables ' be used for representing must be remained under a predetermined value (hereinafter referred to as " set point ") or be remained in a preset range (" setting range ") by Programmable Logic Controller.Set point or setting range need not be fixing (entity) existing.In fact, it often may change (or during cooling calculate, or as predefined procedure in time).As control variables, ' monitored parameters ' measured optionally record, but to compare with control variables, it need not be remained on a set point or be remained in a setting range by Programmable Logic Controller.But monitored parameters can serve as the input of Programmable Logic Controller, make it to make decision according to these monitored parameterses, or produce communication signal, or for example make Programmable Logic Controller give the alarm signal or time-out and/or abandon automated procedure.
Preferably, described one or more control variables comprises following one or more rate of temperature change in time: the refrigerant temperature of a JT valve suction side; The one JT valve is discharged the refrigerant temperature of side; Inner certain the hydrocarbon stream temperature a bit located of cryogenic heat exchanger; Hydrocarbon stream temperature with cryogenic heat exchanger downstream.This provides one directly to show, is further convenient to cooling cryogenic heat exchanger, can not surpass the maximum temperature rate of change of regulation.
Replace or together with rate of temperature change, described one or more control variables can comprise in cryogenic heat exchanger or selected space temperature gradient around.This is convenient to cooling cryogenic heat exchanger, can not surpass the maximum space thermograde of regulation.The suitable space temperature gradient remaining within predetermined maximum is the thermograde between refrigerant pipe and shell wall.
It will be appreciated by those skilled in the art that, maximum temperature rate of change and/or maximum space thermograde depend on type and/or the concrete structure of the heat exchanger that carries out cooling processing conventionally.The concrete recommendation of relevant these values can be provided by manufacturer.
In the situation that cryogenic heat exchanger comprises for the shell-side of vaporized refrigerant with for the pipe side of cooling refrigeration agent automatically, the temperature difference between the pipe side that selected space temperature gradient can reflect the shell-side of cryogenic heat exchanger and comprise cold-producing medium.
Also exist other preferred thermogrades can be used in for example a whole set of formula configuration (line-ups), wherein, in the downstream of cooler and the upstream of a JT valve, one liquid/vapour separator is arranged in cold-producing medium recirculation circuit, in order to the cold-producing medium of receiving unit condensation with by the cold-producing medium stream of this partial condensation, be separated into liquid recasting cryogen part (fraction) and gaseous light cold-producing medium part, and in order to discharge liquid recasting cryogen part via liquid outlet and to discharge gaseous light cold-producing medium part via gas vent, described liquid recasting cryogen part and gaseous light cold-producing medium are partly sent to cryogenic heat exchanger, wherein a JT valve is arranged to control the circulation of in these parts, preferably control the circulation of light cold-producing medium part.
Selected space temperature gradient can reflect one or more in following in the configuration of such the whole series: the temperature difference between the cold-producing medium between the cold-producing medium of consumption and the gas vent of cryogenic heat exchanger and gaseous state refrigerant inlet; And the cold-producing medium and the liquid outlet of cryogenic heat exchanger and the temperature difference between the cold-producing medium between liquid refrigerant entrance that consume.
Other feasible control variables comprise and represent the working condition of one or more compressor, the variable of for example surge condition.So-called surge straggling parameter can be determined according to sensing data, to quantize the surge of compressor and the deviation between actual operating state.Be considered to flow through the flow of associated compressor level and inlet pressure and the discharge pressure of associated compressor level for determining that the typical sensors data of surge straggling parameter comprise.
For automatic cooling cryogenic heat exchanger, described one or more manipulated variable can comprise one or two in following: a big or small JT valve that represents the opening of a JT valve is set; Set with the big or small compressor recycle valve that represents the opening of compressor recycle valve.The opening of the one JT valve directly affects the cooldown rate of cryogenic heat exchanger completely because it be determine JT valve when cold-producing medium stream flows through JT valve to one of factor of its Joule-Thomson effect, it has determined the cooling capacity of cold-producing medium.The opening of compressor recycle valve affects the cooldown rate of cryogenic heat exchanger equally, because because compressor recycle valve is controlled pressure and a kind of mode of flow velocity of cold-producing medium, it also affects JT (joule-Thomson) effect of a JT valve.
Certainly, also exist and can control the pressure of cold-producing medium and/or other manipulated variables of flow, for example compressor speed.Thereby compressor speed also can be used as one of them manipulated variable.But, to compare with speed, valve is to be very suitable for the part handled in pressure being had to relatively more instant control sequence.
Method and apparatus disclosed here can be used for making in the method for hydrocarbon stream liquefaction, for example natural gas flow.Under these circumstances, the cooling of cryogenic heat exchanger normally moves afterwards, and wherein hydrocarbon stream is cooled in cryogenic heat exchanger, until it is liquefied, preferably, after this in cryogenic heat exchanger or the heat exchanger below, carries out supercooling.
Because a lot of reasons, liquefied natural gas stream is desirable.For instance, natural gas liquids, than longer distance storage and transportation of gaseous form, because it has occupied less volume, does not need storage of higher pressures.
Conventionally, natural gas, mainly comprises methane, under high pressure enters LNG station, and carries out pretreatment, to generate, is suitable for the refinery feedstock that liquefies under cryogenic temperature.Utilize heat exchanger that refining gas is processed by a plurality of cooling class, reduce gradually its temperature, until realize liquefaction.Then can select further cooling liquid natural gas, and be expanded to the final atmospheric pressure that is suitable for accumulating by one or more expansion stages.Flash vapors from each expansion stages can be used as factory's fuel gas source.
It should be noted that US 2006/0213223 A1 has disclosed a kind of liquefaction station and method for the production of liquefied natural gas.The control at this liquefaction station can full automation or partial automation, for example, by using suitable computer, programmable logic loop (PLC), using closed loop and open loop policy, usage ratio, integration, differential (PID) to control.But US 2006/0213223 does not have instruction computer program or algorithm as described in the present application.
As being schematically shown in Fig. 1, be provided with a cryogenic heat exchanger 1, it is arranged to receive hydrocarbon stream to be liquefied via pipeline 2 and hydrocarbon stream entrance 7, so as between hydrocarbon stream and the cold-producing medium 3 of at least partly evaporation heat-shift.The result of heat exchange is that hydrocarbon stream at least partly can liquefy.Preferably, the hydrocarbon stream of liquefaction drains in pipeline 4 via hydrocarbon stream outlet 8 at least partly.In drawn embodiment, pipeline 2 is connected via pipe side 29 with pipeline 4.But the heat exchanger of other types is also feasible.
Cryogenic heat exchanger 1 comprises for the refrigerant inlet 5 of external refrigerant with for flowing through the refrigerant outlet 6 of the cold-producing medium consuming of cryogenic heat exchanger.One cold-producing medium recirculation circuit 10 is set, makes consumed cold-producing medium recirculation get back to entrance 5.Cold-producing medium recirculation circuit 10 at least comprises compressor 11, compressor recycle valve 12, cooler 13 and first joule-Tang Pusen (JT) valve 14.
In an embodiment of the present invention, JT valve can be used in combination with expander.But especially in heat exchanger cooling period, JT valve is preferably used for controlling that this is cooling.
In an embodiment of the present invention, compressor can be comprised of a plurality of compression stages, for example 15 compression stages or more compression stage.Several compression stages, for example 15 compression stages, can be arranged on the form of Axial Flow Compressor or centrifugal compressor in a housing.At different levelsly all can comprise a special-purpose recycle valve, and/or the follow-up level of any amount can share single recycle valve.Some compressors or compressor housing be arranged in series and to form be compressor bank one by one.Each housing (or compressor stage) can be selectable cooler (or intercooler) and the selectable cylinder of any amount below, to remove any liquid from compressed steam before compressed steam flows to next compression stage.After last compression stage, can cooling compressed cold-producing medium stream.
But for ease of explanation the present invention, Fig. 1 and 2 has simply described a whole set of configuration of compressor with schematic diagram, has wherein only drawn a compressor and a recycle valve.
When operation, (the evaporating at least partly) cold-producing medium consuming is extracted via outlet 6 from heat exchanger 1, and wherein at least a portion is sent to the suction inlet of compressor 11 via pipeline 25.
The gaseous state part of the cold-producing medium the consuming stream in pipeline 25 is compressed, produce compressed cold-producing medium stream 16, compressed cold-producing medium stream 16 is cooled subsequently in one or more cooler (depicting cooler 13 here as), thereby the compressed cold-producing medium stream 16 of condensation, flows 17 to be formed to the cold-producing medium of small part condensation at least in part.The cold-producing medium stream 17 of this at least part of condensation expands through a JT valve 14, imports in heat exchanger 1 subsequently via entrance 5.
As shown in Figure 1, cold-producing medium stream passes through heat exchanger 1 with hydrocarbon stream (from left to right) stream.But as an alternative, this flows also can be arranged to adverse current, such as the situation of Fig. 2.
In Fig. 2, shown the cryogenic heat exchanger configuration of distortion, it comprises as element identical in the embodiment of Fig. 1, also comprises in addition the refrigerant pipe side 15 for automatic cooling refrigeration agent.Hydrocarbon stream 2 and cold-producing medium both carry out heat exchange by the cold-producing medium of the evaporation in heat exchanger 1.Compressed cold-producing medium stream 16 is cooled subsequently in one or more cooler (depicting cooler 13 here as), then cooling via pipe side 15 in heat exchanger 1, thereby the compressed cold-producing medium stream 16 of condensation, flows 17 to be formed to the cold-producing medium of small part condensation at least in part.The cold-producing medium stream 17 of at least part of condensation that this is automatic cooling is extracted from heat exchanger in outlet 18, before being sent in heat exchanger 1 via entrance 5, imports a JT valve 14, in heat exchanger 1, makes this cold-producing medium stream evaporation at least in part.
Optionally, a cold-producing medium make-up system can be set, it can change the quantity in stock of cold-producing medium, especially the in the situation that of mix refrigerant.
Inventor has been found that the step of cooling cryogenic heat exchanger and the order of task can utilize Programmable Logic Controller described herein to realize ideally automation preferably, and one or more in wherein following is as control variables:
The rate of change of the refrigerant temperature of the-the one JT valve suction side;
The-the one JT valve is discharged the rate of change of the refrigerant temperature of side;
The rate of change of inner certain any the hydrocarbon stream temperature of-cryogenic heat exchanger;
The rate of change of the hydrocarbon stream temperature in-cryogenic heat exchanger downstream;
First temperature difference of the cold-producing medium stream of the-the one JT valve both sides (temperature difference between the cold-producing medium of the cold-producing medium of a JT valve suction side and JT valve discharge side);
The thermograde of the temperature difference between near the cold-producing medium that-reflection consumes (in outlet 6 or pipeline 25 or) and the cold-producing medium at entrance 5 places of cryogenic heat exchanger 1;
The thermograde of the temperature difference between the shell-side 3 of-reflection cryogenic heat exchanger and the pipe side that contains cold-producing medium (such as pipe side 15);
The suction pressure of the cold-producing medium stream of the suction side of-compressor;
And following parameter is used as manipulated variable:
The-the one JT valve is set, for example, represent that the size (X14) of opening amount of a JT valve or a big or small JT valve that flows through the flow of a JT valve set; And/or
-compressor recycle valve is set, for example represent that the size (X12) of opening amount of compressor recycle valve or the big or small compressor recycle valve that flows through the flow of recycle valve set when being provided with make-up system, the replenish valve of refrigerant component also can be used as manipulated variable.
In addition, one or more in following can be used as monitored parameters:
One or more absolute temperature at one or more position in-cryogenic heat exchanger or around; With
-compressor discharge pressure.
Fig. 3 has shown the schematic block diagram being included in for the example modules structure of the computer program of the Programmable Logic Controller of self-cooling method and equipment.The first module 201 limits primary condition.Module 201 can comprise the graphic interface with the summary of warning and information pattern.It can include the information of closing critical and non-critical primary condition.In the situation that there is critical condition, module stops computer program, thereby stops this process.After critical condition solves, or manual by operator, or automatically control control procedure reset primary condition by operation, can recover and/or restart this process.The in the situation that of non-critical primary condition, module 201 is sent a warning.This module can also start the monitoring to critical variable.When whole critical variables are all within preset range, reach module target.Then can produce termination triggering signal.
The example of critical primary condition comprises:
The-the one JT valve 14 does not fully cut out (for example more than 0.1% open or amount that other are applicable);
Pressure in-refrigerant loop is discharged lower than compressor 11;
-compressor 11 does not have on-line operation, and this can for example, be determining of opening by inlet valve and the drain of measuring compressor speed (compressor at least moves under 3400rpm or other suitable speed) and examine on compressor;
-refrigerant pressure too high (for example, higher than 20barg or other suitable numerical value);
-suction port of compressor guide vane (IGV) is opened.
The example of non-critical primary condition comprises:
-various actual temperatures and/or the temperature difference, described actual temperature is for example the refrigerant temperature in a direct upstream of JT valve 14 and direct downstream;
-compressor recycle valve is not opened (being for example less than 99% aperture or other any suitable values) completely; With
-compressed refrigerant pressure is lower than a predetermined minimum value (this may unnecessarily make cooling process slow down).Conventionally, suitable minimum of a value is 18barg.
Obviously, before module 201 can be placed on one or more other modules, be for example placed on be cooled to moderate temperature level or relevant module like that before, and can when receiving one or more triggering signal, start.
Once produce communication signal, this communication signal can be issued and be received by module 202, and module 202 has the module target of first opening a JT valve 14.This may relate to the algorithm of any non-linear behaviour of having considered JT valve.Once cooling trend be detected, this valve will partly cut out, to avoid too high cooling rate.
The communication signal of module 202 (or corresponding signal) trigger module 203, then module 203 only waits for that some times just start.Object is to wait for that described equipment is stable after the first critical action of module 202.Stand-by period can be depending on the end-state of module 202.
Received by two modules 204,205 with the corresponding signal of communication signal of module 203, so these two modules are triggered simultaneously.
Module 204 is further opened a JT valve 14.Especially in the embodiment of Fig. 2, the strong cooling condensation that may cause cold-producing medium.Just, before there is condensation, the valve that preferably slows down moves, and one detects condensation, valve just can partly cut out, to avoid too high cooling rate, in addition, flow that too high cooling rate also may be caused by condensation increases suddenly and causes (within 10 seconds, increasing 100tpd unrare).Detect after condensation, proofread and correct the aperture of valve and continue, until the JT effect of valve opening weakens.This is module target.
Can in the further opening procedure of JT valve, monitor JT effect, for example the temperature difference between the refrigerant temperature based on JT valve upstream and the refrigerant temperature in JT valve downstream.If the temperature difference surpasses 8 ℃, just can suppose and have JT effect.
By the temperature of JT valve and one or two the postponement in flow measurement, can detect condensation.For the cold-producing medium that flows through a JT valve 14, can use the refrigerant temperature in JT valve 14 downstreams and/or flow through the flow of JT valve, this conversely can be by determining that the pressure reduction at JT valve 14 two ends calculate.
In a preferred embodiment, module can not further be closed JT valve 14 than minimum aperture, aperture when this minimum aperture starts corresponding to this module.
While further opening JT valve, the variation of JT effect may be very little.But meanwhile, along with module 205 is carried out its instruction (meanwhile module 204 is also carried out its instruction), refrigerant pressure increases.Module 205 is handled recycle valve 12, to reach the target surge deviation of compressor (or some compression stages).The surge deviation of this module monitors compressor 11, if surge deviation surpasses predetermined maximum deviation, closes recycle valve 12.Suitable predetermined maximum deviation is 0.3.
If there are a plurality of recycle valves, for example, in a plurality of compressor stages, consider the special-purpose surge straggling parameter of corresponding stage, can distinguish (but simultaneously) and handle each recycle valve, each specific recycle valve is controlled recirculation by this.
Because closing of recycle valve 12 affects compressor suction pressure, for example, so this pressure is preferably monitored to be not less than the suggestion limit, a 1.8barg by module 205.Closing of recycle valve makes suction pressure reduce equally.So the precondition that recycle valve is closed is to avoid causing that suction pressure drops to below predetermined target value.Target is, by the Simultaneous Stabilization in monitoring surge deviation close recycle valve so that discharge pressure keeps slope to change (increase).When surge deviation is for example, during lower than thought minimum level (0.1), stopping modular is movable.But surge deviation is all monitored all the time in whole last cooling procedure, when surge deviation allows and suction pressure within preset range time, close recycle valve.
When the temperature of cryogenic heat exchanger 1 meets its operating temperature, in module 204 and 205, produce communication signal, this communication signal is received by module 206.For make it be enough to the heat exchanger of liquefaction for cooling methane, operating temperature can be-160 ℃.In this case, because two modules that stop before module 206 are all in response to the communication signal (temperature that is cryogenic heat exchanger reaches predetermined work temperature) that identical state produces them, the corresponding single triggering signal that mark described state and is sent to described module is considered to the signal corresponding to the communication signal of module and described module.
If surge deviation does not make it to stop appearance, module 206 is closed recycle valve 12 as much as possible completely.If stoping, surge deviation further closes recycle valve, just in case surge value too low (generally lower than 0.1), produce a warning information, and output must be carried out IGV adjustment with alert operator.IGV motion has the effect of closing recycle valve 12 that is similar to.But, can suppress IGV by the mole of cold-producing medium of circulation and move, this mole must surpass a predetermined minimum value.The minimum mole of typical MR is 24g/mol.Obviously, if there is no IGV on the compressor using, this alarm signal may not be one and effectively select.
Because IGV motion is considered to last-resort, attempt is only that alert operator must be carried out IGV motion possibly, rather than any IGV motion is carried out in attempt under the control of automated procedure as above.
In some cases, module 206 may be unnecessary, therefore can dispense, thereby rely on module 205 completely.
Once recycle valve is fully closed or fully closes, just produce communication signal, as shown in Figure 3, for this example, this communication signal is received by module 207.
Module 207 can be a termination module, and it can be programmed and transfers control to operator and/or a State-output be provided or produce operator's alarm signal, to notify operator can carry out the normal operating of cryogenic heat exchanger, etc.But, module 207 can be also the beginning module of control procedure subsequently, for example normal operating is controlled, leading (advanced) process control described in United States Patent (USP) 7266975 and/or United States Patent (USP) 6272882, or the module of any other type.
Except the above-mentioned sequential control for cooling heat exchanger, one or more some that also may embed in monitored parameters and/or control variables surmounts boundary.One or more in monitored parameters crossed one of these boundaries, may cause the signal that gives the alarm, with alert operator or suspend cooling or abandon cooling or these combination.
These exemplary that surmount boundary comprise:
The predetermined maximum temperature rate of change of-relevant any selected temperature, one or more in preferably following: the temperature of the hydrocarbon product of pipe side 29 and/or pipeline 4 interior a certain positions; The temperature of the cold-producing medium consuming; The one JT valve 14 is discharged the refrigerant temperature (especially after automatic cooling) of side or suction side; Any shell-side temperature in heat exchanger 1;
-predetermined maximum space thermograde, the regulation temperature difference in its reflection heat exchanger or between the point that around two spaces separate, preferably, in entrance 5 and/or the cold-producing medium in JT valve 14 downstreams and outlet 6 in or the temperature difference between the cold-producing medium consuming around or in pipeline 25; And the temperature difference between the local temperature in the shell-side of the cold-producing medium in pipe side or hydrocarbon stream and heat exchanger.
The cold-producing medium recirculation circuit one-component refrigerant that can circulate, such as methane, ethane, propane, or nitrogen; Or the multicomponent mix refrigerant of circulation based on two kinds or above component, is called mix refrigerant (MR) sometimes for short.These components can be preferably selected from: nitrogen, methane, ethane, ethene, propane, propylene, butane and pentane.
Refrigerant loop can comprise the independent line of cold-producing medium of any amount of cooling different hydrocarbon streams or common elements or the feature of stream and any amount, comprises compressor, cooler, expander, etc.Some cold-producing medium stream can be public, and some can be independent.In certain embodiments of the invention, the method for described cooling cryogenic heat exchanger for example belongs to, from a part for the method for incoming flow liquefaction hydrocarbon stream (natural gas flow).Equally, equipment described herein also can be used for making in the method for hydrocarbon stream liquefaction.
Hydrocarbon stream can be any applicable hydrocarbonaceous to be liquefied, the stream that preferably contains methane, but it extracts the natural gas flow obtaining in natural gas or oily reservoir conventionally.As an alternative, natural gas flow also can obtain from another source, also comprises comprehensive source, for example Fischer-Tropsch (Fischer-Tropsch) technique.
Conventionally, natural gas consists of methane substantially.Preferably, feed flow comprises at least 60% (mol ratio) methane, more preferably at least 80% (mol ratio) methane.
Hydrocarbon feed flow can liquefy by making it to flow through some cooling class.Can use the cooling class of any amount, each cooling class can comprise one or more heat exchanger and optional one or more step, degree or part.Each cooling class can comprise or two or more heat exchangers of series connection or parallel connection or series connection and parallel combination.
Suitable various types of can be cooling and heat exchanger Liquefied Hydrocarbon feed flow be known in the art, the present invention can be applied to wherein any.The example of such heat exchanger types comprises the heat exchanger that can obtain from Air Products & Chemicals Inc. and Linde AG, generally includes a branch of, two bundles, three beams or multi beam more.
Suitable can be cooling and various being configured in of the heat exchanger of liquefaction feed flow (as the hydrocarbon stream such as natural gas) be known in the art, comprise single mixed refrigerant (SMR) configuration, double-mixed refrigerant (DMR) configuration, propane mix refrigerant configuration (C
3-MR), the configurations based on three or more circulations (for example by Air Products & Chemicals Inc. based on C
3-MR-N
2the so-called APX that circulation is released configures), and comprise that those are with grids (cascade) configuration of Local cooling circulation.The present invention can be applied to such be configured to and configuration that other are suitable in any heat exchanger of any configuration, some small change is within those skilled in the art's scope in power.
In various configurations, the cooling and liquefaction of hydrocarbon feed flow comprises two (or more) cooling class, comprises pre-cooled level and main cooling class.Conventionally, pre-cooled level is cooled to hydrocarbon stream under 0 ℃, and generally between-80 ℃ and-30 ℃, and the second level can be called as main low temperature level, is cooled to below-100 ℃, so that hydrocarbon stream liquefaction.
According to the difference in source, natural gas can comprise the heavy hydrocarbon of ratio methane of variable quantity, such as ethane, and propane, butane and pentane and some aromatic hydrocarbon.Natural gas flow can also comprise nonhydrocarbon, such as H
2o, N
2, CO
2, H
2s and other sulfide, etc.
If needed, hydrocarbon stream can carry out pretreatment before for the present invention.This pretreatment can comprise removes any undesirable component existing, for example CO
2and H
2s, or other steps, for example pre-cooled, precompressed etc.Because these steps are well known to those skilled in the art, so do not discuss further at this.
In addition, those skilled in the art should easily understand, and after liquefaction, liquefied natural gas can further be processed as required.For instance, the liquefied natural gas obtaining can reduce pressure by Joule-Thomson valve or by cryogenic turboexpander.
The present invention can comprise one or more other or other refrigerant loop, for example, in pre-cooled level.Any other or other refrigerant loop can optionally be connected and/or Xiang Bingliu (concurrent) with the refrigerant loop for cooling hydrocarbon stream.
Fig. 4 has shown the cryogenic heat exchanger 100 of larger type, and it is embedded into and has variously by the pre-cooled heat exchanger of another refrigerant loop work and the system of other equipment, and this can find in hydrocarbon liquefaction station.This another refrigerant loop is hereinafter referred to as " pre-cooled refrigerant loop " or " pre-cooled refrigerant circulation ".Equally, parts, for example compressor and cold-producing medium also can be called " pre-cooled refrigeration compressor " or " pre-cooled cold-producing medium ".
Cryogenic heat exchanger 100 in this embodiment is hereinafter referred to as main cryogenic heat exchanger 100, with make it with this embodiment in any other heat exchanger of occurring make a distinction.Main cryogenic heat exchanger 100 comprises temperature end 33, cold junction 50 and medium position 27.The wall of main cryogenic heat exchanger 100 limits shell-side 110.In shell-side 110, be located:
The-the first pipe side 29, it extends to cold junction 50 from temperature end 33, preferably between hydrocarbon stream entrance 7 and hydrocarbon stream outlet 8, extends;
The-the second pipe side 28, it extends to medium position 27 from temperature end 33, preferably from temperature, holds 33 gaseous refrigerant entrance 49a to extend to medium position 27; With
-tri-pipe sides 15, it extends to cold junction 50 from temperature end 33, preferably from temperature, holds 33 liquid refrigerant entrance 49b to extend to cold junction 50.
Provide refrigeration compressor set for compressed refrigerant, as shown here, refrigeration compressor set symbolically comprises the first compressor 30 and the second compressor 31.Each in these compressors is provided with several recycle valves, at this, the recycle valve in a recirculation line 130 and 131 schematically shows these recycle valves, and described recirculation line is connected to low pressure suction inlet by the compressor discharge port of corresponding cooler downstream.
The first refrigeration compressor 30 for example, is driven by suitable motor (gas turbine 35), described gas turbine 35 is provided with the servo-motor 36 for starting, the second refrigeration compressor 31 for example, is driven by suitable motor (gas turbine 37), and described gas turbine 37 is provided with servo-motor (not shown).As selection, compressor 30 and 31 can drive on the single axle of shared motor.
In the normal course of operation after cooling main cryogenic heat exchanger, gaseous state, the temperature that preferably the hydrocarbon feed flow of methane rich is under high pressure supplied to main cryogenic heat exchanger 100 by feeding pipe 20 is held the first pipe side 29 at 33 places.Hydrocarbon feed flow flows through the first pipe side 29, and here, hydrocarbon feed flow leans against in shell-side 110 that the mix refrigerant (MR) of evaporation is cooling, liquefaction and supercooling alternatively, and this mix refrigerant forms the cold-producing medium consuming.The hydrocarbon stream of the liquefaction forming thus removes by pipeline 40 from main cryogenic heat exchanger 100 at cold junction 50.The fluid of hydrocarbon stream in system can utilize and for example be arranged on weakening in pipeline 40 (rundown) valve 44 and control.
Stream 40 can select to flow through suitable end flash system, and wherein pressure drop is to storing pressure and/or transport pressure.Finally, the hydrocarbon stream of liquefaction is transferred into storage unit as product stream,, as liquiefied product storage, or can select direct transportation here.
In normal course of operation, and in the cooling procedure of main cryogenic heat exchanger, the cold-producing medium consuming passes through pipeline 25 at temperature end 33 from the shell-side 110 of main cryogenic heat exchanger 100, and is sent to cylinder 56.
Cold-producing medium supply regulates pipeline 65 to be also fed to cylinder 56, can select to add cold-producing medium quantity in stock to consumed cold-producing medium stream.The interpolation of various refrigerant component can be controlled by one or more valve, a valve for common every kind of component.Here, these valves schematically illustrate as valve 66.
The evaporation section 55 of the cold-producing medium consuming flowing out from the top of cylinder 56 is compressed refrigeration compressor 30 and 31, and to obtain compressed cold-producing medium stream, this cold-producing medium stream removes by pipeline 32.Other refrigeration compressor configurations are also feasible.
Between two refrigeration compressors 30 and 31, the heat of compression removes from flowing through the fluid of pipeline 38 in extraneous cooler 23, and described extraneous cooler 23 can comprise the extraneous cooler of aerial cooler and/or water cooler and/or any other type.Equally, intercooler (not shown) can be set between two of compressor continuous compressor stages.
Compressed cold-producing medium stream in pipeline 32 is cooled in aerial cooler 42, and lean on pre-cooled refrigerant circulation and partly condensation at one or more pre-cooled heat exchanger (being shown as 43 and 41), described pre-cooled circulation will hereafter be described in more detail.Pre-cooled heat exchanger 41,31 can move under mutually different pressure, and/or uses different refrigerant component.
Then, the cold-producing medium of partial condensation stream 39 is transmitted and enters liquid/vapour separator via an inlet device, is depicted as separator flask 45 and inlet device 46 here.In separator flask 45, the cold-producing medium stream of partial condensation is separated into recasting cryogen part (being liquid refrigerant part (HMR)) and light cold-producing medium part (being gaseous refrigerant part (LMR)) here here.These streams can be by means of JT valve or analog, for controlling a JT valve 58 of steam (gently) cold-producing medium stream and controlling respectively for controlling the 2nd JT valve 58 that liquid state (weight) cold-producing medium flows.
Liquid recasting cryogen part removes from separator flask 45 by pipeline 47, and gaseous light cold-producing medium part removes by pipeline 48.Recasting cryogen part in the second pipe side 28 of main cryogenic heat exchanger 100 by supercooling, must be cold recasting refrigerant flow 54.Cross cold recasting refrigerant flow and remove from main cryogenic heat exchanger 100 by pipeline 54, and be caught to expand through an expansion gear, described expansion gear comprises the 2nd JT valve 51.Expansion gear further also can comprise the dynamic swelling device (not shown) of connecting with the 2nd JT valve 51, and it need not be in any cooling procedure manipulate of main cryogenic heat exchanger.
Cross cold recasting refrigerant flow introduces in the shell-side 110 of main cryogenic heat exchanger 100 at medium position 27 by pipeline 52 and nozzle 53 under the pressure reducing.Recasting refrigerant flow is allowed to evaporation in shell-side 110 under the pressure reducing, thus in pipe side 29,28 and 15 cooling these fluids.
The gaseous refrigerant removing from separator flask 45 by pipeline 48 is partly transferred in the 3rd pipe side 15 of main cryogenic heat exchanger 100, and here, it is cooled, liquefaction and supercooling, must be cold light cold-producing medium stream 57.Cross cold light cold-producing medium stream and remove from main cryogenic heat exchanger 100 by pipeline 57, and be caught to expand through an expansion gear, described expansion gear comprises a JT valve 58.Cross cold light cold-producing medium stream introduces in the shell-side 110 of main cryogenic heat exchanger 100 at cold junction 50 by pipeline 59 and nozzle 60 under the pressure reducing.Light cold-producing medium stream is allowed to evaporation in shell-side 110 under the pressure reducing, thus in pipe side 29,28 and 15 cooling these fluids.
(not shown) optionally, selectable effluent can extract from gaseous light cold-producing medium stream 48, and it can be cooling by one or more other cold flows in one or more other heat exchangers except main cryogenic heat exchanger 100, liquefaction and supercooling.For example, it can lean in the stream 40 from the flash system of selectable end that the cold flash-off steam producing is cooling, liquefaction and supercooling.Selectable excessively cold effluent can be again with pipeline 57 or 59 in the combination of light cold-producing medium stream, in such cases, need to assist expander device, for example an auxiliary JT valve.The more detailed explanation of this scheme is referring to United States Patent (USP) 6272882.
Pre-cooled heat exchanger 41,43 uses pre-cooled cold-producing medium operation, and pre-cooled cold-producing medium can be blending ingredients cold-producing medium or one-component refrigerant.For this example, used propane.The propane of evaporation is compressed in pre-cooled compressor 127, and described pre-cooled compressor 127 for example, is driven by suitable motor (gas turbine 128).Be provided with equally a pre-cooled refrigeration compressor recycle valve 129, be symbolically shown as here in connecting the pipeline of first order compressor low pressure suction inlet and intermediate pressure level.But compression stage two ends all or that select can selectively arrange recirculation line.
The condensation in aerial cooler 130 of compressed propane, then the compressed propane of condensation is under high pressure sent to by pipeline 135 and 136 heat exchanger 43 and 41 being arranged in series with each other.Before entering heat exchanger 43, the propane of condensation is allowed to be expanded to an intermediate pressure through expansion valve 138.There, propane partly evaporates by the heat from the multi-component refrigrant in pipeline 32, and the gaseous state part of the evaporation forming is thus transferred into the intermediate pressure entrance of propane compressor 127 by pipeline 141.Liquid part is transferred into heat exchanger 41 by pipeline 145.Before entering heat exchanger 41, propane is allowed to be expanded to a low pressure through expansion valve 148.The propane of evaporation is transferred into the suction inlet of propane compressor 127 by pipeline 150.
It will be appreciated by those skilled in the art that and can cylinder or analog be set being connected on any pipeline of compressor suction, to avoid to the non-gas phase of compressor feeding.One saveall (economizer) also can be set.
In the present example, two shown pre-cooled heat exchangers move under two stress levels.But, also can adopt the pre-cooled heat exchanger of heat and the corresponding stress level of any amount.
Pre-cooled refrigerant circulation also can be for obtaining hydrocarbon stream 20, as described below.Supply pipe 90 is under high pressure flow through in hydrocarbon charging (being natural gas feed in the present example).Natural gas feed (being generally the multicomponent mixture of methane and heavy composition) at least one heat exchanger 93 by partly condensation.
In the present example, this heat exchanger uses the effluent 137 extracting from the pre-cooled cold-producing medium of pipeline 135, under the stress level approximately identical with pre-cooled heat exchanger 43, moves.Although do not draw in Fig. 4, pipeline 137 is connected in pipeline 137a.Before entering heat exchanger 93, pre-cooled cold-producing medium is allowed to be expanded to about intermediate pressure through expansion valve 139.The gaseous state part of the evaporation forming is thus transferred into pipeline 141 by pipeline 140a and 140, and here, it is combined from the gaseous state part of pre-cooled heat exchanger 43 with extraction again.The liquid part of pre-cooled cold-producing medium extracts from heat exchanger 93 in pipeline 151, and is being fed in heat exchanger 91 after valve 152 is expanded to suitable low pressure.The pre-cooled cold-producing medium of evaporation is introduced into pipeline 150 via pipeline 153a and 153.
It should be noted that heat exchanger 43 and 93 and/or heat exchanger 41 and 91 can in pipeline 32, be arranged to comprise for natural gas with for the form of the combination exchanger of the separate sides of cold-producing medium.
The charging 92 of partial condensation is for example introduced into gas/liquid separation 95 via inlet device 94, and described gas/liquid separation 95 can be arranged to the form of scrubbing tower for example or analog.In scrubbing tower 95, the charging of partial condensation is separated, obtains the gaseous overhead stream 97 of methane rich and the liquid tower bottom flow 115 of poor methane.
Gaseous overhead stream 97 is transferred into overhead separator 102 by pipeline 97 via heat exchanger 91.In heat exchanger 100, the partly condensation of pre-cooled cold-producing medium in gaseous overhead stream tube road 151, the overhead streams of partial condensation is introduced into overhead separator 102 via inlet device 103.In overhead separator 102, the overhead streams of partial condensation is separated into gaseous flow 20, and (it is substantially from C
5+ component exhausts and/or compare methane with incoming flow relative abundant) and liquid tower bottom flow 105.Gaseous flow 20 forms the hydrocarbon charging under high pressure in pipeline 20.
At least a portion of liquid tower bottom flow 105 can be introduced scrubbing tower 95 as refluxing by pipeline 105 and nozzle 106.Pipeline 105 is provided with flow control valve (not shown) and/or pump 108.
If the liquid in the gaseous overhead stream 105 of required reflux ratio partial condensation is few, surplus capacity can be transferred into pipeline 20 through bypass line (not shown) and flow control valve (not shown).In the situation that the backflow obtaining very little, external reflux medium (being suitably butane) can add to pipeline 105 from external source (not shown).
Liquid rich C
3+ tower bottom flow via pipeline 115, from scrubbing tower 95, remove.Here can from flow process, extract, in any mode well known by persons skilled in the art, deliver to fractionation (fractionation) group and/or storage unit/Department of Transportation and/or reboiler.
Before normal operation as above, main cryogenic heat exchanger must be cooled to running temperature.The method and apparatus that the present invention discloses has been realized the automatically cooling of main cryogenic heat exchanger.This is proved according to following content.
During cooling processing, by Programmable Logic Controller, can monitor in main cryogenic heat exchanger and around some temperature, rate of temperature change and the temperature difference of each point.This can make Programmable Logic Controller determine that the time dependent curve of temperature develops.Fig. 5 has shown point in main cryogenic heat exchanger 100 and around, wherein, in test, except other temperature and temperature sensor, is provided with temperature sensor (TR20; TR25; TR33; TR40; TR47; TR48; TR52; TR54; TR57; TR59) and temperature sensor (TDR2547; TDR2548; TDR2715; TDR5254; TDR5759), these other temperature and temperature sensor are not further discussed at this, because consider that they and described automation relation are little.
The configuration of the whole series in Fig. 5 is corresponding to the whole series configuration in Fig. 4, but for emphasize corresponding to shown in the reference number of various sensors, omitted the reference number of the whole series configuration in Fig. 5.Temperature sensor is labeled as " TR ", after be corresponding to member of imparting, flow or be provided with the numeral of reference number of the pipeline (pipeline) of sensor.For temperature sensor, used code TDR, after and then corresponding to member of imparting, stream or be provided with two dibit numerals of the pipeline (pipeline) of temperature sensor therebetween.Temperature sensor and temperature sensor produce sensor signal, and described sensor signal can be received and be monitored by Programmable Logic Controller, and Programmable Logic Controller can be used one or more in these as control variables.
At the top of main cryogenic heat exchanger 100, the pipeline 57 of JT valve 58 upstream and downstreams and 59 temperature serviceability temperature sensor TR57 and TR59 monitor.Difference between these temperature is also monitored, for determining as the actual JT effect on a JT valve.
Measure the shell temperature difference at medium position 27 places, and determine that pipe side 15 is in the temperature (TDR2715) at medium position 27 places.In addition, utilize TR33, can measure the temperature of taking from the cold-producing medium consuming of heat exchanger near the shell temperature of temperature end 33 and pipeline 25 (TR25).
The inlet temperature of heavy liquid refrigerant part can utilize TR47 to measure, the inlet temperature that is close to the hydrocarbon stream of main cryogenic heat exchanger 100 upstreams can utilize TR20 to measure, be close to main cryogenic heat exchanger 100 downstreams the temperature that weakens hydrocarbon stream can utilize TR40 to measure.
When there is forward streams, whole temperature surveys is all stable and reliable.For example, thereby measurement may be sometimes unreliable, when turning back to temperature sensor when stagnant gas is beginning to cool down.Original state, for example pressure state are depended in monitoring.
The temperature of indicating cooling end is that hydrocarbon product weakens line temperature TR40.Yet when hydrocarbon stream is minimum, this is measured may be unreliable when cooling beginning.So, when cooling beginning, can monitor another temperature as an alternative, that suitable is the LMR temperature T R59 in JT valve 58 downstreams.Yet when cooling end, fiducial temperature will be TR40.
During cooling processing, by Programmable Logic Controller, can monitor some pressure and the pressure reduction of each point in a whole set of configuration.Maximally related pressure sensor (PR32; PR54; PR55; PR57; PR150) use PR to be illustrated in Fig. 5, be corresponding to member of imparting after PR or be provided with the numeral of reference number of the pipeline (pipeline) of sensor.The most important pressure of monitoring comprises hybrid refrigeration compressor 30 suction pressures (PR55) in pre-cooled compressor suction pressure PR150, pipeline 55 in pipeline 150; With the hybrid refrigeration compressor discharge pressure PR32 in pipeline 32.
These pressure sensors produce the sensor signal that can be received and be monitored by Programmable Logic Controller, and Programmable Logic Controller can be used one or more in these as control variables.
Pressure in a whole set of configuration may affect cooling procedure after long-time shutdown, especially in the situation that the whole series configuration has recycled several days completely.Under high-pressure situations, little variation also has large impact to main cryogenic heat exchanger 100 overall cooling.In addition, PR57 and PR54 LMR and the HMR pipe pressure of a JT valve 58 and the 2nd JT valve 51 upstreams (respectively) can monitor before cooling.If these pressure are too high, any valve dirigibility has dynamic faster, as long as the primary condition that system has stress level is lower than predetermined initial maximum pressure value (in this test, we use 20barg).
To LMR and HMR stream, can calculated flow rate, so that as control variables or at least as variable to be monitored.Such calculating can be based on pressure differential and a JT valve 58 and the 2nd JT valve 51 specified valve opening separately.To this, can utilize the suction pressure (PR55) of the refrigerant loop to the pressure before the first and second JT valves on LMR and two loops of HMR (being respectively PR57 and PR54) and before flowing to compressor to measure.
Standard deviation for the flow measurement of less JT valve opening may be quite large, if as monitored parameters, it can lead to errors.The linear model of least square of whole measurements of the higher valve opening of conduct of linear model that LMR and HMR are mobile calculates.Based on this model, the flow of estimating is by providing as follows:
F
lMR=K
lMRx
58√ (PR57-PR55); With
F
HMR＝K
HMR·X
51·√(PR54-PR55)，
Wherein, F
lMR(F
hMR) represent the flow in LMR pipeline 48 (HMR pipelines 47); X
58(X
51) represent the opening of the first (the second) JT valve 58,51; K
lMR(K
hMR) represent the linear model constants of least square corresponding to slope.Have been found that linear least square model meets desired precision.But, also can adopt the function of other types to substitute.Especially, for HMR, can estimate quadratic function, and flow for LMR, have been found that the character shape that is similar to square root function.
Just to carry out automatically cooling before, first main cryogenic heat exchanger 100 is being precooled to approximately-25 ℃ and the about temperature between-35 ℃ under manually controlling.Other tasks manually complete at present in this level, but these tasks also can automation and is attached in the modular structure that the present invention discloses, described other tasks comprise:
For example, horizontal plane in-any online NGL (natural vapour-liquid, general by the molecular composition with the quality that is comparable to propane and Geng Gao) extraction tower (scrubbing tower) is controlled;
The temperature of-stream 20 is controlled;
The step-down of-refrigerant loop (particularly managing side 15,28);
-gas-defrost/cold air mixture is controlled, for by refrigerant loop tube-cooled to approximately-25 ℃ with about-35 ℃ between temperature.
Main cryogenic heat exchanger is further cooled to approximately-155 ℃ of following operating temperatures, is cooled to the approximately operating temperature of-160 ℃ here, utilizes self-cooling method and equipment to realize.Further coolingly can be known as hereinafter " finally cooling ".
Fig. 6 has shown the modular structure of using in test with schematic diagram.Module 301 defines the primary condition very identical with above-mentioned module 201.The example of critical primary condition comprises:
-if what handle is that hydrocarbon stream (is allowed the C of maximum 0.08% (mol ratio) conventionally
5+), there is excessive heavy constituent in (for example, in pipeline 20) in hydrocarbon charging;
The-the first and second JT valves (58,51) fully do not cut out (in this test, using the opening value that surpasses 1%);
Pressure in-refrigerating circuit (LMR and HMR) is discharged lower than compressor 31;
-one or more refrigeration compressor 30,31 and pre-cooled refrigeration compressor 127 do not have on-line operation (for example detecting by compressor speed);
Inlet valve and dump valve on-these compressors are not opened;
-the refrigerant pressure of compressor 31 discharges place too high (test is used and is 20barg to the maximum);
The suction pressure of-pre-cooled refrigeration compressor 127 has exceeded predetermined pressure window (about 0.5barg window around suitably);
Any IGV valve of-existence does not fully cut out.
The example of non-critical primary condition comprises:
-TDR5759 too little (in the situation that from the coil exchanger of Air Products & Chemicals Inc, the typical minimum of a value of recommending is 25 ℃);
-one or more refrigeration compressor recycle valve (for example 130,131) is not opened (in this test, use and be less than 99% degree of opening) completely;
The discharge pressure of-compressor 31 is lower than a predetermined minimum value (having been used 18barg in this test).
The signal trigger module 308 of one communication signal corresponding to module 301.Module 302 is also triggered by the same signal of the communication signal corresponding to module 301.
The first module in module 302 mark module sub-networks, module sub-network refers to module 303,304,305 and 309 to 312 here.Therefore, the whole sub-network of following module all with module 308 parallel work-flows and and stream.
As first module 202 opens JT valve 14, first module 302 itself opens a JT valve 58.
Module 303 is triggered by module 302, and then it waits for some times, the spitting image of module 203 as above.Module 305,305,309 and 310 is received when the signal of the communication signal corresponding to module 303 and is triggered.
As the JT valve 14 described in module 204, module 304 is further also opened a JT valve 58.
Module 305 regulates compressor recycle valve (or valve) 131, the same the spitting image of the module 205 of above-mentioned adjusting recycle valve 12.
But, in addition, also there is module 309, it moves in network under the level identical with module 305, and described module 309 close compressor recycle valves 130, when preferably response represents that the predetermined temperature of main low-temperature heat exchange actuator temperature has reached predetermined value.Closing by surge deviation of compressor recycle valve 130 suppresses, and described surge deviation is partly subject to the impact of module 304 and 310 to 312.Thereby in fact, module 309 makes refrigerant pressure maximum as much as possible, and maintains the surge deviation of allowing simultaneously.
Preferably, predetermined temperature is temperature T R57, and this predetermined value is designed to, and certainly, the automatic cooling LMR flowing in pipeline 57 and 52 and HMR part, by total condensation, make not closing of recycle valve can cause cooling rate is produced to less desirable impact.For example, predetermined temperature value can be-135 ℃, but this depends on the composition of used multi-component refrigrant.Certainly, too low surge deviation can form the restriction that recycle valve is closed.May produce an information to operator, that is, must carry out IGV and move.
In addition, module 309 can comprise computer executable instructions, with before reaching predetermined value in temperature, closes recycle valve 130, but closing of recycle valve can be triggered by other emergencies.In the situation of the surge deviation that another emergency may appear at compressor 30 for example higher than predetermined maximum (being generally 0.3).Excessive surge deviation can cause the physical vibration of compressor, even if therefore also do not reach predetermined temperature, also will close recycle valve 130.
Module 310 is controlled opening first of the 2nd JT valve 51.It is opened into is enough to make than only setting up by a JT valve 58 cooling trend faster of moving.The 2nd JT valve 51 open first the algorithm that relates to any non-linear behaviour of having considered that this valve is opened first.The attempt of this module remains on below maximum limit initial cooling rate, at this, is coolingly no faster than 28 ℃/h.Yet due to the nonlinear characteristic of JT valve when opening at first (as mentioned above), this is impossible.In this case, this process continues minimum cooling rate as much as possible, the cooling rate that it reaches when minimum is opened as seen corresponding to JT valve.State when this module starts is present in clearly in temperature profile, and this temperature profile can be regarded as rate of temperature change standardization the cooling distribution map of TR54.So this module and module 304 are activated simultaneously.Altogether, this module is combined in network and moves under same level with module 304 with module 311 (it is triggered by following module 310).
In order to set up the cooling trend of increase, module 310 is at predetermined time interval, for example per minute, opens the 2nd JT valve, until chilling temperature detected, changes (in this test, until cooling rate detected faster than 0.1 ℃/h).Then shut off valve 51 marginally.And then check that this is cooling, be sure of that the 2nd JT valve 51 does not cut out again or cooling be not too fast.If too fast, will further close the 2nd JT valve.If cooling trend stops, opening this valve, until cooling trend is set up again.Within reaching preset range stablize cooling trend time, produce communication signal.
Communication signal from module 310 is received by module 311, and this communication signal trigger module 312 also.Module 311 is moved further the 2nd JT valve 51.Consider three kinds of situations:
I), more than condensation scope, control the 2nd JT valve position;
Ii) there is condensation in the recasting cryogen in pipeline 54, and any JT valve motion all slows down;
Iii) when condensation being detected, the 2nd JT valve 51 cuts out a little, with the high cooling rate of avoiding being flowed and being caused by condensation.After heavy condensation of refrigerant in pipeline 54 being detected, the flow-control of recasting cryogen is being utilized on the remote setting point of flow controller setting.The rate of temperature change of TR54 and the temperature of TR25 will be determined the step-length (step) of flow controller set point.The final temperature target of TR54 and TR25 is moved stop valve.
When the maximum temperature of for example TR57 or TR40 has reached its desired value, module 311 completes.Any contribution from recasting cryogen to cooling task reduces from that time, except leaveing no choice but regulate cold-producing medium supply.
Supply regulates to be controlled by module 312, and as mentioned above, the communication signal producing based on module 310 and trigger module 312, to start with module 311 simultaneously.Module handle supply with:
Gradient along head for target operating pressure (in this test, being 30barg) increases compressor 31 discharge pressures;
Towards target, form (target composition), mobile cold-producing medium forms, and it can be target end or the intermediate objective of main cryogenic heat exchanger 100 normal operations that described target forms.
During cooling procedure, cold-producing medium target forms and can change.When control variables reaches predetermined value, cold-producing medium target forms and can change gradually or in step-length mode.For example, once temperature T R57 drops to below the predetermined value of-135 ℃ or-140 ℃, just can change.
In test process, nitrogen is the specific part of supply.Nitrogen supply is preferably only carried out when having an opportunity, for example, in MR compressor 30 suction pressures low (for example, lower than 2.0barg).This is to be only about 2barg because test period nitrogen is supplied with pressure.
Module 312 has certain durability (robustness) (for example, due to the communication failure between instrument and DCS, or due to sensor fault) in the situation that the methane total amount in MR stream is obtained to reliable measurements inefficacy, and this is quite general.Under these circumstances, not direct measurement, but by supposing that all the other are methane, according to C
2(ethane), C
3(propane) and N
2composition estimation methane form.
Whole sub-network as above (comprising module 303,304,305 and 309 to 312) is made as a whole and module 308 executed in parallel, module 308 regulates one or more in pre-cooled refrigeration compressor recycle valve, here the form with first order recycle valve 129 regulates, and described first order recycle valve 129 is controlled by the recirculation flow of the first compression stage of compressor 127.Module target is to make within the suction pressure of relevant pre-cooled cold-producing medium suction pressure (in the pipeline 150 of Fig. 4) remains on a preset range, 0.25-0.50barg for example, but can not make surge deviation reduce to obtain too close control line.The temperature that low pressure can guarantee to enter the hydrocarbon air inlet of main cryogenic heat exchanger 100 (for example, via pipeline 20) has a reasonable value.So the temperature in pipeline 20 itself does not need monitoring or is used as the condition for controlling in this module.
In addition, the discharge temperature of pre-cooled refrigeration compressor 127 (in pipeline 135) is not monitored yet, because the automatic cooling procedure of using in test does not provide the ability of any variable of the situation that can handle the high discharge temperature that can be used for improving pre-cooled refrigeration compressor 127.But, implement this monitoring and also can not depart from the scope of the present invention.
One or more some that can embed for monitored parameters surmounts boundary.One or more in monitored parameters crossed one of these boundaries (surpass predetermined maximum and/or minimum of a value), may cause the signal that gives the alarm, and with alert operator, suspends cooling or abandons cooling or both combinations.
These exemplary that surmount boundary comprise:
The predetermined maximum temperature rate of change (for example 28 ℃/h of Air Products cryogenic heat exchanger defined) of-relevant any selected temperature, one or more in preferably following: the temperature of the hydrocarbon product of pipe side 29 and/or discharge line 40 interior a certain positions; The temperature of the cold-producing medium consuming (for example, in the bottom Wen Duanzhong or pipeline 25 of shell-side 33); The one JT valve 58 or the 2nd JT valve 51 are discharged the refrigerant temperature of side or suction side; Any shell-side temperature in heat exchanger 1;
-predetermined maximum space thermograde, regulation maximum temperature difference (for example maximum temperature difference of 28 ℃) in its reflection heat exchanger or between the point that around two spaces separate, temperature difference TDR2547 between the light cold-producing medium of preferred main cryogenic heat exchanger 100 upstreams and the cold-producing medium consuming (can also be TDR3347, not show); Temperature difference TDR2548 between the recasting cryogen of main cryogenic heat exchanger 100 upstreams and the cold-producing medium consuming (can also be TDR3348, not show); TDR2715; And TDR5759;
The predetermined maximum level (0.08% (mol ratio)) of the heavy constituent that can freeze in main cryogenic heat exchanger 100 in the incoming flow of-hydrocarbon;
Inlet valve and dump valve on-refrigeration compressor are closed;
The maximum prescribed shell pressure on top surface (5barg) of-main cryogenic heat exchanger cold junction;
-detection accidental shutdown (trip);
In-control system, there is communication error.
Obviously, also can use other to surmount boundary, for example, in the situation that use the cryogenic heat exchanger of other types.
Lower Table I has shown the whole variablees that are used as manipulated variable in this test, and lower Table II has shown in this test with acting on the control variables of decision-making or whole variablees of monitored parameters.
Table I: manipulated variable
Table II: control variables and monitored parameters
By handling mix refrigerant flow, composition and the first and second JT valves, automated procedure for last cooling main cryogenic heat exchanger as above has reduced the bulk temperature of main cryogenic heat exchanger gradually, has determined the compression ratio through these JT valve flash distillations the first and second JT valve portions.
Although do not implement in this test, but expect, comprise other first front module or subsequent module or both larger module networks in further embed the modular structure similar modular structure of another a whole set of configuration or heat exchanger (or for) of Fig. 6.Fig. 7 has shown the example being embedded in subsequent module.
Fig. 7 has shown the modular structure with cooling task after some.For example, can be the middle task that need to complete before control can being taken over for the automatic process control system of normal operation.For example, module 401 is handled and is weakened valve 44, and target is that the flow gradient that flows through pipeline 20,40 and hydrocarbon pipe side 29 is upwards increased.
Other manipulated variables relevant in this grade comprise that all manipulated variables of cooling class add possible IGV and any pre-cooled refrigeration compressor recycle valve as mentioned above, and pre-cooled refrigeration compressor recycle valve is not included in manipulated variable in automatically carrying out cooling.
Preferably, LMR and HMR handle and carry out based on flow-control rather than valve opening.
In addition, manipulated variable can comprise any backflow of relevant online NGL extraction.But, can envision, can after hydrocarbon feed rate reach normal range of operation, by normal level, control and take over.
Other modules thereby can be in parallel with module 401.For instance, although described module 402, but it also comprises it can being the module for any fractionation section gradient is upwards increased, and described any fractionation section can be arranged on the downstream of all NLG extraction towers, to receive and the further NLG liquid of fractional extraction.Those skilled in the art should be able to, according to used the whole series configuration and the type of equipment, design and can use which manipulated variable and control variables.
Equipment described herein and method can be applied to cryogenic heat exchanger, cooling as long as cryogenic heat exchanger need to carry out before operation.This can be for example initially cooling, or maintenance operation after or accidental shutdown after cooling: to the application of theme described herein, it doesn't matter than the warmer reason of running temperature for heat exchanger.
It will be appreciated by those skilled in the art that, the present invention can be in the situation that do not depart from the scope of subsidiary claims and implement in many different modes.The present invention is depicted in greater detail, is included as some control variables desired value is provided.But, for a person skilled in the art, it is evident that, the selection of these values configures and device-dependent with the concrete the whole series for testing.In another a whole set of configuration of using other equipment, implement when of the present invention, such details may need to be optimized, so such details should not be considered to the restriction to scope of the present invention.
Claims (22)
1. the equipment for cooling cryogenic heat exchanger, described cryogenic heat exchanger is applicable to make hydrocarbon stream liquefaction, described cryogenic heat exchanger is arranged to receive hydrocarbon stream to be liquefied and cold-producing medium, and can make hydrocarbon stream and cold-producing medium carry out heat exchange, thereby make at least in part hydrocarbon stream liquefaction, and can be expelled to the hydrocarbon stream of small part liquefaction and by the cold-producing medium consuming of cryogenic heat exchanger, this equipment comprises:
-make consumed cold-producing medium recirculation get back to the cold-producing medium recirculation circuit of cryogenic heat exchanger, described cold-producing medium recirculation circuit at least includes compressor, compressor recycle valve, cooler and first joule-Tang Pusen valve;
-Programmable Logic Controller, it is arranged to
(i) receive input signal, described input signal represents the sensor signal of one or more control variables;
(ii) generate control signal to control one or more manipulated variable; With
(iii) computer program, described computer program comprises the network with at least three modules, one or more in wherein said at least three modules receives one or more the expression in input signal, and generates one or more the expression in control signal;
And wherein said at least three modules are all arranged to:
(a) wait for, until receive a triggering signal; With
(b), when receiving triggering signal, start to carry out the predefined procedure of one or more computer-readable instruction, at least until reach the predetermined module target of this module;
And, these module interconnects in network, the communication signal producing while making triggering signal correspondence that the second and the 3rd module in described at least three modules receives the first module in described at least three modules reach the predeterminated target of this module.
2. equipment as claimed in claim 1, wherein, the mutual parallel work-flow of the second and the 3rd module, thus, the control action of one in the described second and the 3rd module is subject to the constraint of a variable, and this variable is subject to one or more manipulated variables effect of at least another manipulation in the second module and the 3rd module.
3. equipment as claimed in claim 1, wherein, described one or more control variables comprises rate of temperature change in time.
4. equipment as claimed in claim 3, wherein, rate of temperature change in time comprises one or more in following: the refrigerant temperature of first joule-Tang Pusen valve suction side; First joule-Tang Pusen valve is discharged the refrigerant temperature of side; Inner certain the hydrocarbon stream temperature a bit located of cryogenic heat exchanger; The hydrocarbon stream temperature in cryogenic heat exchanger downstream.
5. equipment as claimed in claim 1, wherein, described one or more control variables comprises in cryogenic heat exchanger or selected space temperature gradient around.
6. equipment as claimed in claim 5, wherein, selected space temperature gradient reflects one or more in the following temperature difference: the temperature difference between the cold-producing medium at the refrigerant inlet place of the cold-producing medium of consumption and cryogenic heat exchanger; The temperature difference between the cold-producing medium of the cold-producing medium of first joule-Tang Pusen valve suction side and discharge side.
7. equipment as claimed in claim 1, wherein, cryogenic heat exchanger comprises for the shell-side of vaporized refrigerant with for the pipe side of cooling refrigeration agent automatically.
8. equipment as claimed in claim 5, wherein, cryogenic heat exchanger comprises for the shell-side of vaporized refrigerant with for the pipe side of cooling refrigeration agent automatically.
9. equipment as claimed in claim 8, wherein, the temperature difference between the shell-side of described selected space temperature gradient reflection cryogenic heat exchanger and the pipe side that comprises cold-producing medium.
10. equipment as claimed in claim 1, wherein, in the downstream of cooler and the upstream of first joule-Tang Pusen valve, one liquid/vapour separator is arranged in cold-producing medium recirculation circuit, in order to the cold-producing medium of receiving unit condensation with by the cold-producing medium stream of this partial condensation, be separated into liquid recasting cryogen part and gaseous light cold-producing medium part, and in order to discharge liquid recasting cryogen part via liquid outlet and to discharge gaseous light cold-producing medium part via gas vent, described liquid recasting cryogen part and gaseous light cold-producing medium are partly sent to cryogenic heat exchanger, wherein first joule-Tang Pusen valve is arranged to control a kind of circulation in liquid recasting cryogen part and gaseous light cold-producing medium part described in these.
11. equipment as claimed in claim 10, wherein, described a kind of in described liquid recasting cryogen part and gaseous light cold-producing medium part is gaseous light cold-producing medium part.
12. equipment as claimed in claim 5, wherein, in the downstream of cooler and the upstream of first joule-Tang Pusen valve, one liquid/vapour separator is arranged in cold-producing medium recirculation circuit, in order to the cold-producing medium of receiving unit condensation with by the cold-producing medium stream of this partial condensation, be separated into liquid recasting cryogen part and gaseous light cold-producing medium part, and in order to discharge liquid recasting cryogen part via liquid outlet and to discharge gaseous light cold-producing medium part via gas vent, described liquid recasting cryogen part and gaseous light cold-producing medium are partly sent to cryogenic heat exchanger, wherein first joule-Tang Pusen valve is arranged to control a kind of circulation in liquid recasting cryogen part and gaseous light cold-producing medium part described in these,
Wherein, one or more in following of selected space temperature gradient reflection: the temperature difference between the cold-producing medium between the cold-producing medium of consumption and the gas vent of cryogenic heat exchanger and gaseous state refrigerant inlet; The cold-producing medium and the liquid outlet of cryogenic heat exchanger and the temperature difference between the cold-producing medium between liquid refrigerant entrance that consume.
13. equipment as claimed in claim 1, wherein, described one or more control variables comprises one or two in following: first temperature difference of the cold-producing medium stream of first joule-Tang Pusen valve both sides; Suction pressure with the cold-producing medium stream of the suction side of compressor.
14. equipment as claimed in claim 1, wherein, cryogenic heat exchanger comprises for the outlet of the hydrocarbon stream entrance of hydrocarbon stream and hydrocarbon stream, and one or more the separated refrigerant inlet and the refrigerant outlet that are respectively used to cold-producing medium and consumed cold-producing medium.
15. as the equipment as described in arbitrary in aforementioned claim, and wherein, described one or more manipulated variable at least comprises one or two in following: the big or small first joule-Tang Pusen valve that represents the opening of first joule-Tang Pusen valve is set; With any pressure setting of controlling the refrigerant pressure of first joule-Tang Pusen valve upstream.
16. equipment as claimed in claim 15, wherein, described pressure setting comprises the big or small compressor recycle valve setting of the opening that represents compressor recycle valve.
17. 1 kinds of methods for cooling cryogenic heat exchanger, described cryogenic heat exchanger is applicable to make hydrocarbon stream liquefaction, and the method comprises the following steps:
-cryogenic heat exchanger is provided, described cryogenic heat exchanger is arranged to receive hydrocarbon stream to be liquefied and cold-producing medium, and can make to carry out between hydrocarbon stream and cold-producing medium heat exchange, thereby hydrocarbon stream is liquefied at least in part, and can be expelled to the hydrocarbon stream of small part liquefaction and by the cold-producing medium consuming of cryogenic heat exchanger
-provide one to make consumed cold-producing medium recirculation get back to the cold-producing medium recirculation circuit of cryogenic heat exchanger, described cold-producing medium recirculation circuit at least includes compressor, compressor recycle valve, cooler and first joule-Tang Pusen valve valve;
-activation one Programmable Logic Controller, described Programmable Logic Controller
(i) receive the input signal of the sensor signal that represents one or more control variables;
(ii) generate control signal to control one or more manipulated variable; With
(iii) computer program, described computer program comprises the network with at least three modules, one or more in wherein said at least three modules receives one or more the expression in input signal, and generates one or more the expression in control signal;
And, each in wherein said at least three modules
(a) wait for, until receive a triggering signal; With
(b), when receiving triggering signal, start to carry out the predefined procedure of one or more computer-readable instruction, at least until reach the predetermined module target of this module;
And wherein, the first module in described at least three modules produces a communication signal while reaching the predeterminated target of this module, described communication signal passes to the second and the 3rd module in described three or more modules, and there, communication signal serves as second and the triggering signal of the 3rd module.
18. methods as claimed in claim 17, wherein, described hydrocarbon stream is natural gas flow.
19. 1 kinds of methods for hydrocarbon stream is liquefied, it comprises the following steps:
-according to the method described in claim 17, a cooling cryogenic heat exchanger, described cryogenic heat exchanger is applicable to make hydrocarbon stream liquefaction;
-in one or more step, make hydrocarbon stream liquefaction subsequently, comprise and at least make hydrocarbon stream in cryogenic heat exchanger, carry out heat exchange.
20. methods as claimed in claim 19, wherein, described hydrocarbon stream is natural gas flow.
21. 1 kinds of methods for hydrocarbon stream is liquefied, it comprises step:
-right to use requires arbitrary described equipment in 1 to 16, a cooling cryogenic heat exchanger, and described cryogenic heat exchanger is applicable to make hydrocarbon stream liquefaction;
-in one or more step, make hydrocarbon stream liquefaction subsequently, comprise and at least make hydrocarbon stream in cryogenic heat exchanger, carry out heat exchange.
22. methods as claimed in claim 21, wherein, described hydrocarbon stream is natural gas flow.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP08101424.3 | 2008-02-08 | ||
| EP08101424 | 2008-02-08 | ||
| PCT/EP2009/051353 WO2009098278A2 (en) | 2008-02-08 | 2009-02-06 | Method and apparatus for cooling down a cryogenic heat exchanger and method of liquefying a hydrocarbon stream |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102405389A CN102405389A (en) | 2012-04-04 |
| CN102405389B true CN102405389B (en) | 2014-12-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200980104368.XA Expired - Fee Related CN102405389B (en) | 2008-02-08 | 2009-02-06 | Method and apparatus for cooling down a cryogenic heat exchanger and method of liquefying a hydrocarbon stream |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US20100326133A1 (en) |
| KR (1) | KR20100120184A (en) |
| CN (1) | CN102405389B (en) |
| AU (1) | AU2009211380B2 (en) |
| BR (1) | BRPI0907488B8 (en) |
| MY (1) | MY155810A (en) |
| RU (1) | RU2495343C2 (en) |
| WO (1) | WO2009098278A2 (en) |
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| AU2013203120B2 (en) * | 2012-09-18 | 2014-09-04 | Woodside Energy Technologies Pty Ltd | Production of ethane for startup of an lng train |
| EP2857782A1 (en) | 2013-10-04 | 2015-04-08 | Shell International Research Maatschappij B.V. | Coil wound heat exchanger and method of cooling a process stream |
| EP3058326B1 (en) * | 2013-10-15 | 2018-08-08 | Shell International Research Maatschappij B.V. | Method of monitoring an air operated heat exchanger |
| US10765968B2 (en) | 2014-08-19 | 2020-09-08 | Supercritical Fluid Technologies, Inc. | Systems and methods for supercritical fluid chromatography |
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| US10006587B2 (en) * | 2014-10-06 | 2018-06-26 | L'air Liquide Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Argon recondensing method |
| WO2016107822A1 (en) * | 2014-12-29 | 2016-07-07 | Shell Internationale Research Maatschappij B.V. | Method and apparatus for cooling down a cryogenic heat exchanger and method of liquefying a hydrocarbon stream |
| CA2976629C (en) | 2015-03-05 | 2023-05-23 | Shell Internationale Research Maatschappij B.V. | Methane oxidation catalyst, process to prepare the same and method of using the same |
| US10393429B2 (en) * | 2016-04-06 | 2019-08-27 | Air Products And Chemicals, Inc. | Method of operating natural gas liquefaction facility |
| CA3031299A1 (en) | 2016-07-26 | 2018-02-01 | Shell Internationale Research Maatschappij B.V. | Method and apparatus for cooling down a cryogenic heat exchanger |
| SG11201901346YA (en) | 2016-08-31 | 2019-03-28 | Shell Int Research | Methane oxidation catalyst, process to prepare the same and method of using the same |
| AU2017318277B2 (en) | 2016-08-31 | 2019-12-05 | Shell Internationale Research Maatschappij B.V. | Methane oxidation catalyst, process to prepare the same and method of using the same |
| WO2018071884A1 (en) * | 2016-10-14 | 2018-04-19 | Supercritical Fluid Technologies, Inc. | Cooling loop with a supercritical fluid system using compressed refrigerant fluid flow with a positive joule-thomson coefficient |
| CN106766670A (en) * | 2017-01-06 | 2017-05-31 | 四川杰瑞恒日天然气工程有限公司 | natural gas refrigeration system and method |
| SG11202000720TA (en) * | 2017-08-24 | 2020-03-30 | Exxonmobil Upstream Res Co | Method and system for lng production using standardized multi-shaft gas turbines, compressors and refrigerant systems |
| US11946915B2 (en) | 2019-01-04 | 2024-04-02 | Supercritical Fluid Technologies, Inc. | Interchangeable chromatography cartridgeadapter system |
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Also Published As
| Publication number | Publication date |
|---|---|
| WO2009098278A2 (en) | 2009-08-13 |
| AU2009211380B2 (en) | 2012-05-03 |
| CN102405389A (en) | 2012-04-04 |
| BRPI0907488B1 (en) | 2020-08-04 |
| RU2495343C2 (en) | 2013-10-10 |
| MY155810A (en) | 2015-11-30 |
| AU2009211380A1 (en) | 2009-08-13 |
| KR20100120184A (en) | 2010-11-12 |
| RU2010137319A (en) | 2012-03-20 |
| US20100326133A1 (en) | 2010-12-30 |
| BRPI0907488A2 (en) | 2015-07-14 |
| BRPI0907488B8 (en) | 2020-08-18 |
| WO2009098278A3 (en) | 2014-10-02 |
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